A sled with mass 15 kg moves in a straight line on a horizontal surface as it is being pulled by a force F at an angle of 30° with the direction of motion. A force of friction of 10 N acts on the sled. At one point in its path, its speed is 4.0 m/s; after it has traveled a distance 5.0 m beyond this point, its speed is 7.0 m/s. Use the work-energy theorem to find the total work done on the sled?
Find the pulling force F on the sled.

Apoint charge +q is at the origin. a spherical gaussian surface centered at the origin encloses +q. so does a cubical surface centered at the origin and with edges parallel to the axes. select "true" or "false" for each statement below. the electric flux through the spherical surface is greater than that through the cubical surface. suppose (for this statement only), that q is moved from the origin but is still within both the surfaces. the flux through both surfaces remains unchanged. the area vector and the e-field vector point in the same direction for all points on the spherical surface. the e-field at all points on the spherical surface is equal due to spherical symmetry. the flux through the spherical gaussian surface is independent of its radius.